// Copyright (c) 2012 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef NET_SPDY_SPDY_PROXY_CLIENT_SOCKET_H_
#define NET_SPDY_SPDY_PROXY_CLIENT_SOCKET_H_

#include <stddef.h>
#include <stdint.h>

#include <list>
#include <string>

#include "base/macros.h"
#include "base/memory/ref_counted.h"
#include "base/memory/weak_ptr.h"
#include "net/base/completion_callback.h"
#include "net/base/host_port_pair.h"
#include "net/base/load_timing_info.h"
#include "net/http/http_auth_controller.h"
#include "net/http/http_request_headers.h"
#include "net/http/http_request_info.h"
#include "net/http/http_response_info.h"
#include "net/http/proxy_client_socket.h"
#include "net/log/net_log.h"
#include "net/spdy/spdy_http_stream.h"
#include "net/spdy/spdy_protocol.h"
#include "net/spdy/spdy_read_queue.h"
#include "net/spdy/spdy_session.h"
#include "net/spdy/spdy_stream.h"

namespace net {

class AddressList;
class HttpStream;
class IOBuffer;
class SpdyStream;

class NET_EXPORT_PRIVATE SpdyProxyClientSocket : public ProxyClientSocket,
                                                 public SpdyStream::Delegate {
public:
    // Create a socket on top of the |spdy_stream| by sending a SYN_STREAM
    // CONNECT frame for |endpoint|.  After the SYN_REPLY is received,
    // any data read/written to the socket will be transferred in data
    // frames. This object will set itself as |spdy_stream|'s delegate.
    SpdyProxyClientSocket(const base::WeakPtr<SpdyStream>& spdy_stream,
        const std::string& user_agent,
        const HostPortPair& endpoint,
        const HostPortPair& proxy_server,
        const BoundNetLog& source_net_log,
        HttpAuthController* auth_controller);

    // On destruction Disconnect() is called.
    ~SpdyProxyClientSocket() override;

    // ProxyClientSocket methods:
    const HttpResponseInfo* GetConnectResponseInfo() const override;
    HttpStream* CreateConnectResponseStream() override;
    const scoped_refptr<HttpAuthController>& GetAuthController() const override;
    int RestartWithAuth(const CompletionCallback& callback) override;
    bool IsUsingSpdy() const override;
    NextProto GetProtocolNegotiated() const override;

    // StreamSocket implementation.
    int Connect(const CompletionCallback& callback) override;
    void Disconnect() override;
    bool IsConnected() const override;
    bool IsConnectedAndIdle() const override;
    const BoundNetLog& NetLog() const override;
    void SetSubresourceSpeculation() override;
    void SetOmniboxSpeculation() override;
    bool WasEverUsed() const override;
    bool WasNpnNegotiated() const override;
    NextProto GetNegotiatedProtocol() const override;
    bool GetSSLInfo(SSLInfo* ssl_info) override;
    void GetConnectionAttempts(ConnectionAttempts* out) const override;
    void ClearConnectionAttempts() override { }
    void AddConnectionAttempts(const ConnectionAttempts& attempts) override { }
    int64_t GetTotalReceivedBytes() const override;

    // Socket implementation.
    int Read(IOBuffer* buf,
        int buf_len,
        const CompletionCallback& callback) override;
    int Write(IOBuffer* buf,
        int buf_len,
        const CompletionCallback& callback) override;
    int SetReceiveBufferSize(int32_t size) override;
    int SetSendBufferSize(int32_t size) override;
    int GetPeerAddress(IPEndPoint* address) const override;
    int GetLocalAddress(IPEndPoint* address) const override;

    // SpdyStream::Delegate implementation.
    void OnRequestHeadersSent() override;
    SpdyResponseHeadersStatus OnResponseHeadersUpdated(
        const SpdyHeaderBlock& response_headers) override;
    void OnDataReceived(std::unique_ptr<SpdyBuffer> buffer) override;
    void OnDataSent() override;
    void OnTrailers(const SpdyHeaderBlock& trailers) override;
    void OnClose(int status) override;

private:
    enum State {
        STATE_DISCONNECTED,
        STATE_GENERATE_AUTH_TOKEN,
        STATE_GENERATE_AUTH_TOKEN_COMPLETE,
        STATE_SEND_REQUEST,
        STATE_SEND_REQUEST_COMPLETE,
        STATE_READ_REPLY_COMPLETE,
        STATE_OPEN,
        STATE_CLOSED
    };

    void LogBlockedTunnelResponse() const;

    // Calls |callback.Run(result)|. Used to run a callback posted to the
    // message loop.
    void RunCallback(const CompletionCallback& callback, int result) const;

    void OnIOComplete(int result);

    int DoLoop(int last_io_result);
    int DoGenerateAuthToken();
    int DoGenerateAuthTokenComplete(int result);
    int DoSendRequest();
    int DoSendRequestComplete(int result);
    int DoReadReplyComplete(int result);

    // Populates |user_buffer_| with as much read data as possible
    // and returns the number of bytes read.
    size_t PopulateUserReadBuffer(char* out, size_t len);

    State next_state_;

    // Pointer to the SPDY Stream that this sits on top of.
    base::WeakPtr<SpdyStream> spdy_stream_;

    // Stores the callback to the layer above, called on completing Read() or
    // Connect().
    CompletionCallback read_callback_;
    // Stores the callback to the layer above, called on completing Write().
    CompletionCallback write_callback_;

    // CONNECT request and response.
    HttpRequestInfo request_;
    HttpResponseInfo response_;

    // The hostname and port of the endpoint.  This is not necessarily the one
    // specified by the URL, due to Alternate-Protocol or fixed testing ports.
    const HostPortPair endpoint_;
    scoped_refptr<HttpAuthController> auth_;

    std::string user_agent_;

    // We buffer the response body as it arrives asynchronously from the stream.
    SpdyReadQueue read_buffer_queue_;

    // User provided buffer for the Read() response.
    scoped_refptr<IOBuffer> user_buffer_;
    size_t user_buffer_len_;

    // User specified number of bytes to be written.
    int write_buffer_len_;

    // True if the transport socket has ever sent data.
    bool was_ever_used_;

    // Used only for redirects.
    bool redirect_has_load_timing_info_;
    LoadTimingInfo redirect_load_timing_info_;

    const BoundNetLog net_log_;

    // The default weak pointer factory.
    base::WeakPtrFactory<SpdyProxyClientSocket> weak_factory_;

    // Only used for posting write callbacks. Weak pointers created by this
    // factory are invalidated in Disconnect().
    base::WeakPtrFactory<SpdyProxyClientSocket> write_callback_weak_factory_;

    DISALLOW_COPY_AND_ASSIGN(SpdyProxyClientSocket);
};

} // namespace net

#endif // NET_SPDY_SPDY_PROXY_CLIENT_SOCKET_H_
